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1.
Opt Express ; 25(14): 15687-15698, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-28789082

RESUMO

In order to overcome the shortages of the target image restoration method for longitudinal laser tomography using self-calibration, a more general restoration method through backscattering medium images associated with prior parameters is developed for common conditions. The system parameters are extracted from pre-calibration, and the LIDAR ratio is estimated according to the medium types. Assisted by these prior parameters, the degradation caused by inhomogeneous turbid media can be established with the backscattering medium images, which can further be used for removal of the interferences of turbid media. The results of simulations and experiments demonstrate that the proposed image restoration method can effectively eliminate the inhomogeneous interferences of turbid media and achieve exactly the reflectivity distribution of targets behind inhomogeneous turbid media. Furthermore, the restoration method can work beyond the limitation of the previous method that only works well under the conditions of localized turbid attenuations and some types of targets with fairly uniform reflectivity distributions.

2.
Opt Express ; 25(7): 7392-7401, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28380861

RESUMO

Target images recorded with range-gated laser imaging systems and conventional passive imaging systems through rapidly changing turbid mediums inevitably suffer from inhomogeneous degradations. Consequently, this makes the images partly or entirely different from their true targets and eventually has adverse effects on target identification. To date, the inhomogeneous degradations are still not finely eliminable despite utilizing adaptive optical methods and pure mathematical signal improvement techniques. Herein, we demonstrate an image restoration method involving intrinsic physical evolution of light beams based on the backscattering images of a turbid medium. The corresponding mathematical signal processing algorithms are applied for restoring the true target images in the presence of rapidly changing inhomogeneous degradations. This technique would benefit target imaging through moving cloud/mist in air and flowing muddy masses under water.

3.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 33(3): 365-9, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23713252

RESUMO

OBJECTIVE: To study the effects of Bushen Zhuyun Decoction (BZD) on the reproductive capacity of mice. METHODS: Totally 60 female Kunming mice were randomly divided into the experimental group and the control group. BZD was perfused by gastric tube to mice in the experimental group, twice daily. Meanwhile, mice in the control group were administered with normal saline by gastrogavage. Mice were sacrificed on the 10th day and the 20th day of medication respectively, 15 mice each time in each group. The serum levels of estradiol and progesterone were detected by radioimmunoassay. The morphological changes of uterus and ovary were observed using HE staining. The expressions of leukaemia inhibitory factor (LIF), epidermal growth factor (EGF), and calcitionin (CT) were determined using immunohistochemical assay. RESULTS: Compared with the control group at the same time point, the weights of uterus and ovary increased, the serum levels of estradiol and progestogen increased, the expressions of LIF, CT, and EGF increased in the experimental group on the 10th day and the 20th day of medication (P <0.05, P <0.01). Better results were shown on the 20th day of medication (P <0.05). Histological results showed increased ovarian follicle numbers, increased endometrial gland numbers, endometrial hyperplasia (stratiform arranged), and increased stromal cells in the experimental group, especially on the 20th day of medication. CONCLUSION: BZD could improve the reproductive capacity by advancing the development of generative organs, promoting the secretion of estradiol and progestogen and the follicular growth, and increasing the receptivity of endometrium.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Endométrio/metabolismo , Ovário/efeitos dos fármacos , Útero/efeitos dos fármacos , Animais , Estradiol/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos , Tamanho do Órgão , Progesterona/metabolismo
4.
Appl Opt ; 51(16): 3590-8, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22695598

RESUMO

In most spacecraft, there is a need to know the craft's angular rate. Approaches with least squares and an adaptive Kalman filter are proposed for estimating the angular rate directly from the star tracker measurements. In these approaches, only knowledge of the vector measurements and sampling interval is required. The designed adaptive Kalman filter can filter out noise without information of the dynamic model and inertia dyadic. To verify the proposed estimation approaches, simulations based on the orbit data of the challenging minisatellite payload (CHAMP) satellite and experimental tests with night-sky observation are performed. Both the simulations and experimental testing results have demonstrated that the proposed approach performs well in terms of accuracy, robustness, and performance.

5.
Appl Opt ; 50(12): 1735-44, 2011 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-21509065

RESUMO

Star pattern recognition and attitude determination accuracy is highly dependent on star spot location accuracy for the star tracker. A star spot location estimation approach with the Kalman filter for a star tracker has been proposed, which consists of three steps. In the proposed approach, the approximate locations of the star spots in successive frames are predicted first; then the measurement star spot locations are achieved by defining a series of small windows around each predictive star spot location. Finally, the star spot locations are updated by the designed Kalman filter. To confirm the proposed star spot location estimation approach, the simulations based on the orbit data of the CHAMP satellite and the real guide star catalog are performed. The simulation results indicate that the proposed approach can filter out noises from the measurements remarkably if the sampling frequency is sufficient.

6.
Fertil Steril ; 93(3): 999-1005, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19108825

RESUMO

OBJECTIVE: To establish reliable methods for cryopreservation of human embryonic stem cells (hESCs). DESIGN: Prospective experimental study. SETTING: University laboratory. PATIENT(S): One hESC line. INTERVENTION(S): The attachment rates and recovery rates of cryopreserved hESCs using three different cryopreservation methods were compared. MAIN OUTCOME MEASURE(S): The hESCs were frozen and thawed by conventional cryopreservation, programmable cryopreservation, and vitrification method. The efficiency of cryopreservation was assessed by attachment rate and recovery rate. RESULT(S): The attachment rate and recovery rate after thawing of hESCs frozen by the conventional cryopreservation method were significantly lower than those of hESCs frozen by programmed cryopreservation and vitrification methods. Vitrification resulted in the highest attachment rate and recovery rate compared with the other two methods. Human ESCs after vitrification and programmable cryopreservation still expressed pluripotent markers, maintained normal karyotype, and retained their pluripotency. CONCLUSION(S): Our data show that programmable cryopreservation and vitrification methods are appropriate for cryopreservation of hESCs, whereas the conventional slow-rate freezing method is not appropriate for cryopreservation of hESCs.


Assuntos
Criopreservação/métodos , Células-Tronco Embrionárias/citologia , Células-Tronco Pluripotentes/citologia , Biomarcadores/metabolismo , Adesão Celular , Células-Tronco Embrionárias/fisiologia , Humanos , Cariotipagem , Células-Tronco Pluripotentes/fisiologia , Temperatura Ambiente , Teratoma/patologia
7.
Neuroreport ; 19(15): 1451-5, 2008 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-18797296

RESUMO

We established a human embryonic stem cell line derived from frozen human embryos of Chinese origin. The cell line expressed the pluripotent markers SSEA-4, TRA-1-60, TRA-1-81, Oct-4, and alkaline phosphatase. The pluripotency of the cell line was also demonstrated in vivo by teratoma formation in severe combined immunodeficiency mice. The embryonic stem cells formed embryoid bodies after culturing in suspension for 7 days. The embryoid bodies were transferred to an adherent culture system in serum-free medium. The differentiating cells derived from the embryoid bodies expressed Nestin and Sox2, markers of neural progenitor cells. After the induction of cyclic AMP for 7 days, the neural progenitor cells had differentiated into neurons and glial cells.


Assuntos
Biomarcadores/análise , Diferenciação Celular , Células-Tronco Embrionárias/metabolismo , Células-Tronco Pluripotentes/metabolismo , Animais , Antígenos de Superfície/análise , Técnicas de Cultura de Células/métodos , Linhagem Celular , Células Cultivadas , Células-Tronco Embrionárias/citologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Glicoesfingolipídeos/análise , Humanos , Imuno-Histoquímica , Cariotipagem , Camundongos , Camundongos SCID , Neuroglia/citologia , Neuroglia/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Fator 3 de Transcrição de Octâmero/análise , Células-Tronco Pluripotentes/citologia , Proteoglicanas/análise , Antígenos Embrionários Estágio-Específicos , Transplante de Células-Tronco , Teratoma/metabolismo , Teratoma/patologia , Transplante Heterólogo
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